Response Surface Methodology Approach for Predicting Convective/Infrared Drying, Quality, Bioactive and Vitamin C Characteristics of Pumpkin Slices

Fatemeh Joudi-Sarighayeh; Yousef Abbaspour-Gilandeh; Mohammad Kaveh; Mariusz Szymanek; Ryszard Kulig

doi:10.3390/foods12051114

Response Surface Methodology Approach for Predicting Convective/Infrared Drying, Quality, Bioactive and Vitamin C Characteristics of Pumpkin Slices

Foods. 2023 Mar 6;12(5):1114. doi: 10.3390/foods12051114.

Authors

Fatemeh Joudi-Sarighayeh¹, Yousef Abbaspour-Gilandeh¹, Mohammad Kaveh², Mariusz Szymanek³, Ryszard Kulig⁴

Affiliations

¹ Department of Biosystems Engineering, College of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil 56199-11367, Iran.
² Department of Petroleum Engineering, College of Engineering, Knowledge University, Erbil 44001, Iraq.
³ Department of Agricultural, Forest and Transport Machinery, University of Life Sciences in Lublin, Głęboka 28, 20-612 Lublin, Poland.
⁴ Department of Food Engineering and Machines, University of Life Sciences in Lublin, Głęboka 28, 20-612 Lublin, Poland.

Abstract

In this research, a convective/infrared (CV/IR) dryer was used to dry pumpkin slices. For optimization of the drying conditions, the influence of three levels of independent variables including air temperature (40, 55, and 70 °C), air velocity (0.5, 1, and 1.5 m/s), and IR power (250, 500, and 750 W) were assessed by response surface method (RSM) through a face-centered central composite design. Analysis of variance (non-fitting factor and R² value) was employed to determine the desirability of the model. Response surfaces and diagrams were also utilized to show the interactive influence of the independent variables with the response variables (drying time, energy consumption, shrinkage, total color variation, rehydration ratio, total phenol, antioxidant, and vitamin C contents). According to the results, optimal drying conditions involved a temperature of 70 °C, air velocity of 0.69 m/s, and IR power of 750 W. At the mentioned conditions, response variables of drying time, energy consumption, shrinkage, color, rehydration ratio, total phenol, antioxidant, and vitamin C contents were 72.53 min, 24.52 MJ/kg, 23%, 14.74, 4.97, 617.97 mg GA/100 g dw, 81.57%, and 4.02 mg/g dw, with a confidence level of 0.948, respectively.

Keywords: RSM; drying; pumpkin; shrinkage; total phenolic content.

Grants and funding

This research was funded by the University of Mohaghegh Ardabili, Iran. Publication was co-financed by the state budget under the program of the Ministry of Education and Science (Republic of Poland) under the name Excellent Science—Support for Scientific Conferences entitled “XXIII Polish Nationwide Scientific Conference “PROGRESS IN PRODUCTION ENGINEERING” 2023” project number DNK/SP/546290/2022 amount of funding 162,650.00 PLN.